It is known to use a brace or splint to support a joint which has undergone either an operation, been injured or is the subject of a long existing medical condition. Different joints require different braces to support the joint, each being adapted accordingly. Braces can be used on both the upper and lower extremities of the human body. One joint which is particularly susceptible to injury and problems, and which often requires surgery, is the shoulder. The shoulder is a complex joint with many bones, tendons, muscles and the like. After injury or surgery, it is often necessary to immobilize the shoulder to avoid or restrict movement and in turn aid the healing process.
Current existing braces for shoulders are cumbersome and give rise to a number of problems both from a practical point of view and a medical point of view. Typically shoulder braces are adapted to maintain the shoulder in a fixed position by strapping the arm in some way to the body by means of straps, belts, suspenders, and the like. The position of the arm relative to the body will depend upon the type of problem the patient has. In some cases the forearm will be across the body, in other cases the forearm will be extended upwards and in other situations the forearm may extend horizontally from the body in line with the shoulder. Typical types of existing braces are shown in FIG. 1.
Some of the problems associated with the existing braces are discussed below. One problem with existing braces is that they are very complicated to use. It is very difficult if not impossible for the patient to put on or remove the brace alone and help is generally required to position the brace correctly.
It is also difficult to find a brace that fits all patients. This generally means there are different braces for different sized people. As a result it is necessary to have a number of different sized braces, this adds to the costs of the design and manufacture and means that the hospital or doctor's surgeries need to stock many braces of different sizes.
Most of the existing braces completely immobilize the upper limb (as required) and the forearm tends to be confined within a portion of the brace, which completely captures the forearm by means of a circumferential tube with straps. The elbow joint is typically maintained at about 90° and the forearm is restricted and practically unable to move. This can lead to a number of problems such as elbow stiffness, stagnation of edema and hematoma, swelling, paresthesia, vein thrombosis and the like. In addition, compartment syndrome in the forearm may occur. The fact that the upper limb is rigidly held in a fixed position may also be detrimental to future joint function and may result in tissue atrophy. In most existing braces there are straps which go round the neck and the back the patient and can cause chafing of the skin and in some cases the sensation of strangulation.
If the patient were to attempt to extend the elbow and straighten the arm, any such movement would typically bring about a forward projection of the shoulder. This can provide a source of pain by tensioning the soft tissue and disturbing any bone fracture fragments being repaired. If this occurs in the early stages of recuperation, when lying down, the reattachment sutures can be compromised and the tendons and ligaments may become detached. This is particularly the case for surgery to repair the rotator cuff, Bankart lesions or osteosynthesis. It should be noted that the current braces do not provide the facility for the patients' to move the elbow, but trying to do so inadvertently can result in the problem identified above.
Due to the nature of existing braces, patients often find sleeping difficult and uncomfortable. With the elbow at 90° flexion in most situations, the hand extends upwards when the patient is sleeping. This can lead to numbness and lack of blood flow in the hands and lower arm. In addition, the elbow and wrist can become stiff due to lack of movement.
Most existing shoulder braces immobilize the shoulder's internal rotation, which may causes harmful consequences to the tendons and ligaments and bones as highlighted below.
For healing tendons of the rotator cuff, the arm position adopted using existing shoulder braces typically does not match the natural rest position or the muscular balance and tendon positions of the shoulder. This gives rise to tensioning of the external rotator muscles and shrinkage of the internal rotator muscles and the rotator interval.
For healing the lesions of the labrum and glenohumeral ligaments in the case of anterior and posterior shoulder instability, immobilization in internal rotation may cause medial scarring of the labrum, which is a recurrent source of anterior instability of the shoulder. Conversely, the neutral rotation or external rotation works in favor of closing the Bankart separation and the healing of the labrum is in a good position.
For healing fractures of the proximal humerus, immobilization of internal rotation of the shoulder after a fracture of the proximal humerus leads to consolidation in a faulty position: for instance malunion in the internal rotation in diaphyseal fractures of the surgical neck and tuberosity malunion in fractures having 3 or 4 fragments can lead to posteromedial migration of the tochiter and anteromedial migration of the lesser tuberosity.